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Colleen H. Hunt Alison B. Smith David R. Jordan Brian R. Cullis 《Journal of Agricultural, Biological & Environmental Statistics》2013,18(1):53-63
There are two key types of selection in a plant breeding program, namely selection of hybrids for potential commercial use and the selection of parents for use in future breeding. Oakey et al. (in Theoretical and Applied Genetics 113, 809–819, 2006) showed how both of these aims could be achieved using pedigree information in a mixed model analysis in order to partition genetic effects into additive and non-additive effects. Their approach was developed for field trial data subject to spatial variation. In this paper we extend the approach for data from trials subject to interplot competition. We show how the approach may be used to obtain predictions of pure stand additive and non-additive effects. We develop the methodology in the context of a single field trial using an example from an Australian sorghum breeding program. 相似文献
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Carprofen, a non-steroidal anti-inflammatory drug (NSAID), was injected intravenously in six cows after calving, either as a single or a daily dose of 0.7 mg/kg for five days. Carprofen was well tolerated by the cows at this dose rate, the milk production and biochemical variables remaining within the normal ranges. The plasma elimination half-life of carprofen ranged from 44.5 to 64.6 h after repeated daily injections. These values are longer than those reported for other NSAIDs used in veterinary medicine, e.g. flunixin and phenylbutazone. The volume of distribution and the clearance values calculated after a single intravenous injection amounted to 0.09 l/kg and 9.0 ml/min. The concentration of carprofen in milk collected twice daily (morning and evening) was, in general, below the sensitivity limit of the analytical method (25 ng/ml) up to five days after the last carprofen injection; the concentration of carprofen reached about 30 ng/ml in only a few milk samples collected after the fourth or fifth injection. This indicates that carprofen is poorly excreted in the milk. 相似文献
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Benchmark study on glyphosate‐resistant cropping systems in the United States. Part 7: Effects of weed management strategy (grower practices versus academic recommendations) on the weed soil seedbank over 6 years 下载免费PDF全文
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Jordan DS 《Science (New York, N.Y.)》1901,14(363):936-937
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The light interception capabilities of individual conifer needles are governed by their cross-sectional geometry and their orientation to sunlight. Leaf cross sections typical of conifer tree species were modeled to quantify the interception of direct sunlight over a range of incident light angles. The needle shapes exhibited by Abies nordmanniana Spach, Picea asperata Master, Pinus cembra L., P. monophylla Torr & Frém., and P. sylvestris L. were selected because they are representative of the range of geometric shapes found in conifer tree species. Calculated light interception values were compared to corresponding predictions for a laminar broadleaf. Estimates of carbon gain were derived from computed incident light integrated over the leaf cross section and a representative curve of conifer photosynthetic response to light. Flat leaf cross sections (e.g., Abies nordmanniana) with high surface area to volume ratios (> 6) intercepted more light per unit area at high angles of incidence than thick leaves. Thick leaves (e.g., Pinus cembra) intercepted more light at low angles of incidence than at high angles of incidence. Needles of Pinus monophylla had no angular dependence for light interception because of their circular cross section. Large differences in estimated CO(2) assimilation occurred among the species, especially when CO(2) uptake was expressed on a unit volume basis. A maximum uptake of 67.9 mmol CO(2) m(-3) s(-1) was predicted for A. nordmanniana compared to a minimum of 39.7 mmol m(-3) s(-1) for P. monophylla. A greater angular dependence occurred for estimates of CO(2) uptake than for estimates of light interception. 相似文献